Significant Improvement of Mechanical Properties in NiAl-Cr(Mo)/Hf Alloy by Suction Casting and Subsequent Hot Isostatic Pressing
Significant Improvement of Mechanical Properties in NiAl-Cr(Mo)/Hf Alloy by Suction Casting and Subsequent Hot Isostatic Pressing
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DOI：
10.1007/s11661-006-9005-5
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发表时间：
2007-01
期刊：
影响因子：
--
通讯作者：
J. Guo;K. Huai;H. Li
中科院分区：
文献类型：
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作者：
J. Guo;K. Huai;H. Li
采用吸铸（SC）和热等静压（HIP）工艺制备了NiAl-28Cr-5.5Mo-0.5Hf共晶合金，并在300 ~ 1373 K温度范围内进行了抗压强度和断裂行为测试。吸铸合金的显微组织表现为层间间距小，共晶晶面积大，晶界处半连续分布有细小的Heusler （Ni2AlHf）相。经HIP处理后，胞界处的Ni2AlHf相转变为Hf固溶相，并均匀分布在NiAl基体内。与常规铸造合金相比，经HIP处理后吸铸合金的室温压缩应变和高温强度均有显著提高。原因是HIP处理使Hf固溶相均匀分布，强化NiAl基体。
The NiAl-28Cr-5.5Mo-0.5Hf eutectic alloy was prepared by the suction casting (SC) technique and subsequent hot isostatic pressing (HIP) treatment, and tested for compressive strength and fracture behavior in the temperature range of 300 to 1373 K. The microstructure of suction-cast alloy is characterized by fine interlamellar spacing, large area fraction of eutectic cell, and fine Heusler (Ni2AlHf) phase distributed semicontinuously at the cell boundaries. After HIP treatment, Ni2AlHf phase at the cell boundaries is transformed into Hf solid solution phase and distributed homogeneously within the NiAl matrix. Compared with the conventionally cast alloy, the room-temperature compressive strain and elevated temperature strength of suction-cast alloy are enhanced markedly after HIP treatment. The reason is that the HIP treatment causes Hf solid solution phase to distribute homogeneously and then strengthens the NiAl matrix.